void ReplaceBlank(char str[], int len)
{
	if (str == NULL || len < 0)
		return;

	int orig = 0;
	int num = 0;
	int i = 0;
	while (str[i] != '\0')
	{
		++orig;
		if (str[i] == ' ')
			++num;
		++i;
	}

	int newlen = orig + num * 2;
	if (newlen > len)
		rerurn ;

	int index = orig;
	int indexo = newlen;
	while (index >= 0 && indexo > index)
	{
		if (str[index] == ' ')
		{
			str[indexo--] = '0';
			str[indexo--] = '2';
			str[indexo--] = '%';
		}
		else { str[indexo--] = str[index]; }
		--index;
	}
}